RS232 comms to Windows host

Projects Programming
1

Hi
Hoping someone might be able to help. I am wanting to interface my Uno with a Windows morse code program called CWCOM. The CWCOM software allows the physical connection of a morse key through an RS232 port and "abuses" the signalling protocol. Specifically the program reads the "Data set ready", "Data Terminal ready" and "Clear to send" pins to which the morse key is connected. I note that my UNO shows a specific COM port when I connect to the programming environment and wondered if those control lines (CTS, DSR etc.) are available by simple commands on the UNO? That way I can use the UNO to interact with CWCOM.
Thanks for any help!
Paul

2

the arduino interfaces to the PC thru a USB interface and has no control over CTS or DSR.

3

The Uno outputs a positive 0v to 5V signal whilst RS232 uses a much higher voltage of both polarities

In principal there is no reason why you could not connect 3 Uno pins to the inputs of the morse key and output signals to it via a voltage level shifter

4

while Arduino uses a USB interface, seems Bob is suggesting that the Arduino could drive the CTS and DSR pins of an RS-232 interface on a PC. there are transceiver chips with charge pumps that can translate the 5V arduino outputs to the higher rs-232 levels

5

That is indeed what I was suggesting because as has been said, the Uno has no direct control over the CTS or DSR pins of the interface

The Morse key is very likely only acting as a switch, probably de-bounced, to toggle the values on the RS232 pins

6

Thanks for your help everyone. Yes, the morse key is a switch which toggles the serial control lines.... the software recognises this and acts accordingly. The CTS, DSR etc. lines are not being used in their "proper" sense and no serial data (as such) flows down the data lines. I was hoping I could send these fake control commands from my UNO via the virtual COM port (that is Arduino connected to my PC via USB) and therefore send morse to CWCOM directly. This is part of a project to read morse from a radio receiver sending audio into one of the analogue-in's on the UNO. From your comments, it seems that sending RTS, DSR etc. is a non-starter. I shall look into a USB/serial converter and check out voltage compatibility with the RS232 standard. Cheers again for your help!
All the best
Paul

7

This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.